DPP QR Codes: Size, Placement and Print Quality

The most fragile part of a Digital Product Passport is not the data model — it is the label. An unreadable QR code is, in practice, a passport that does not exist. EN 18220 sets requirements for encoding, scannability, durability, print quality and placement.

Size and modules

Readability depends less on total size than on module size (the edge of one square). A practical guide:

On very small textile labels, Data Matrix is more efficient. See Data Matrix and direct part marking.

URL length grows the code

The number of modules depends on how many characters you encode. GS1 Digital Link URIs get long with serial numbers, and every extra character either grows the code or shrinks the module.

Practical measures:

• Keep the domain short (id.brand.com, not www.brandsdigitalproductpassport.com).
• Avoid unnecessary query parameters.
• Keep error correction at level M; higher levels enlarge the code.

Quiet zone and contrast

The two most common mistakes:

1. Insufficient quiet zone: leave at least four modules of blank space around the code. Designers often treat it as wasted space.
2. Low contrast: the code must be dark on a light background. Metallic, transparent or patterned substrates confuse scanners.

Placement

• Textiles: woven label, care label or inside seam. A swing tag disappears after sale, so a permanent carrier is needed. See DPP labelling for apparel.
• Electronics: on the body or in the battery compartment, reachable by the user.
• Industrial products: beside the nameplate, laser-marked.
• Packaging: a code on the box is not sufficient on its own — packaging is discarded. See packaging DPP and PPWR.

Durability testing

An obligation to stay readable for the product's lifetime means the label has to last that long. Test:

• Textiles: scanning after 30 wash cycles.
• Outdoor use: contrast after UV and humidity exposure.
• Industrial: after oil, heat and abrasion.

Frequently asked questions